Customer networks are networks established by individuals or companies for internal communication. Customer networks may include local area network (LAN), wide area networks (WAN), and the like. The customer networks may meet customer-specific needs using a number of different communication protocols, such as Asynchronous Transfer Mode (ATM) protocol, frame relay protocols and the like. ATM and frame relay protocols, for example, are frequently used for transport of audio, video, and computer data between a source and destination device within a customer network. Such protocols may transfer information in units, such as frames.
To transfer the frames, switches within a customer network create a fixed path, referred to as a virtual circuit. The frames transmitted by a source device within the customer network travel along the virtual circuit created by the switches. A destination device receives the frames from the virtual circuit, and reassembles the information from the frames. The fixed paths allow customer network equipment to readily allocate and manage the bandwidth required to transmit video, audio, and computer data over the same customer network.
Another popular network technology is the Internet Protocol (IP) networking protocol in which information is divided into blocks called packets. In contrast to frame-based protocols, such as ATM and frame relay, IP-based networks individually route these packets, also referred to as datagrams, across the network from a source device to a destination device. In other words, unlike the virtual circuits within a customer network, each packet can take a different route from the source to the destination device within the IP network. The destination device extracts the information from the packets, and assembles the information into its original form.
In order to allow remote customer networks to communicate, IP-based communication techniques are being developed that relay frames through an IP network, such as the Internet. According to the techniques, ingress routers to the IP network can receive frames from one of the customer networks, encapsulate the frames within packets, and route the packets through the IP network to the other customer network.